[PATCH 0/4] arm64: dts: st: enable camera on stm32mp2x-dk and correct stm32mp2x-ev

[PATCH 0/4] arm64: dts: st: enable camera on stm32mp2x-dk and correct stm32mp2x-ev

[Alain Volmat]

This series enables the camera pipeline on stm32mp235f-dk and
stm32mp257f-dk boards via usage of the CSI IMX335 sensor connected
to the CSI / DCMIPP of the STM32MP2x.
It also perform 2 corrections to the stm32mp257f-ev1 board to ensure
that the IMX335 is well enabled.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
---
Alain Volmat (4):
      arm64: dts: st: add imx335/csi/dcmipp nodes on stm32mp257f-dk
      arm64: dts: st: ensure IMX335 is enabled on stm32mp257f-ev1
      arm64: dts: st: use video-interfaces media bus type in stm32mp257f-ev1
      arm64: dts: st: add imx335/csi/dcmipp nodes on stm32mp235f-dk

 arch/arm64/boot/dts/st/stm32mp235f-dk.dts  | 75 ++++++++++++++++++++++++++++++
 arch/arm64/boot/dts/st/stm32mp257f-dk.dts  | 74 +++++++++++++++++++++++++++++
 arch/arm64/boot/dts/st/stm32mp257f-ev1.dts | 45 +++++++-----------
 3 files changed, 165 insertions(+), 29 deletions(-)
---
base-commit: 2f92d900f262a16c8ae02daf53ae2910d07185f5
change-id: 20260913-stm32mp2-dk-camera-7ad3ac8d3075

Best regards,
--  
Alain Volmat <alain.volmat@foss.st.com>

[PATCH 1/4] arm64: dts: st: add imx335/csi/dcmipp nodes on stm32mp257f-dk

[Alain Volmat]

Add all nodes necessary for the imx335 camera capture via csi / dcmipp
on stm32mp257f discovery board.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
---
 arch/arm64/boot/dts/st/stm32mp257f-dk.dts | 74 +++++++++++++++++++++++++++++++
 1 file changed, 74 insertions(+)

diff --git a/arch/arm64/boot/dts/st/stm32mp257f-dk.dts b/arch/arm64/boot/dts/st/stm32mp257f-dk.dts
index 8daf3dfd5133..39ad23d95069 100644
--- a/arch/arm64/boot/dts/st/stm32mp257f-dk.dts
+++ b/arch/arm64/boot/dts/st/stm32mp257f-dk.dts
@@ -9,6 +9,7 @@
 #include <dt-bindings/gpio/gpio.h>
 #include <dt-bindings/input/input.h>
 #include <dt-bindings/leds/common.h>
+#include <dt-bindings/media/video-interfaces.h>
 #include "stm32mp257.dtsi"
 #include "stm32mp25xf.dtsi"
 #include "stm32mp25-pinctrl.dtsi"
@@ -27,6 +28,14 @@ chosen {
 		stdout-path = "serial0:115200n8";
 	};
 
+	clocks {
+		clk_ext_camera: clk-ext-camera {
+			#clock-cells = <0>;
+			compatible = "fixed-clock";
+			clock-frequency = <24000000>;
+		};
+	};
+
 	gpio-keys {
 		compatible = "gpio-keys";
 
@@ -138,6 +147,42 @@ &arm_wdt {
 	status = "okay";
 };
 
+&csi {
+	vdd-supply =  <&scmi_vddcore>;
+	vdda18-supply = <&scmi_v1v8>;
+	status = "okay";
+
+	ports {
+		#address-cells = <1>;
+		#size-cells = <0>;
+		port@0 {
+			reg = <0>;
+			csi_sink: endpoint {
+				remote-endpoint = <&imx335_ep>;
+				data-lanes = <1 2>;
+				bus-type = <MEDIA_BUS_TYPE_CSI2_DPHY>;
+			};
+		};
+		port@1 {
+			reg = <1>;
+			csi_source: endpoint {
+				remote-endpoint = <&dcmipp_0>;
+			};
+		};
+	};
+};
+
+&dcmipp {
+	status = "okay";
+
+	port {
+		dcmipp_0: endpoint {
+			remote-endpoint = <&csi_source>;
+			bus-type = <MEDIA_BUS_TYPE_CSI2_DPHY>;
+		};
+	};
+};
+
 &ethernet1 {
 	pinctrl-0 = <&eth1_rgmii_pins_b>;
 	pinctrl-1 = <&eth1_rgmii_sleep_pins_b>;
@@ -160,6 +205,16 @@ phy1_eth1: ethernet-phy@1 {
 	};
 };
 
+&gpiob {
+	/* Enable the IMX335 power line */
+	imx335-en-hog {
+		gpio-hog;
+		gpios = <11 GPIO_ACTIVE_HIGH>;
+		output-high;
+		line-name = "imx335_en";
+	};
+};
+
 &i2c2 {
 	pinctrl-names = "default", "sleep";
 	pinctrl-0 = <&i2c2_pins_b>;
@@ -172,6 +227,25 @@ &i2c2 {
 	/delete-property/dmas;
 	/delete-property/dma-names;
 
+	imx335: camera@1a {
+		compatible = "sony,imx335";
+		reg = <0x1a>;
+		clocks = <&clk_ext_camera>;
+		avdd-supply = <&scmi_v3v3>;
+		ovdd-supply = <&scmi_v3v3>;
+		dvdd-supply = <&scmi_v3v3>;
+		reset-gpios = <&gpiob 1 (GPIO_ACTIVE_LOW | GPIO_PUSH_PULL)>;
+
+		port {
+			imx335_ep: endpoint {
+				remote-endpoint = <&csi_sink>;
+				clock-lanes = <0>;
+				data-lanes = <1 2>;
+				link-frequencies = /bits/ 64 <594000000>;
+			};
+		};
+	};
+
 	ili2511: ili2511@41 {
 		compatible = "ilitek,ili251x";
 		reg = <0x41>;

-- 
2.34.1

[PATCH 2/4] arm64: dts: st: ensure IMX335 is enabled on stm32mp257f-ev1

[Alain Volmat]

Set the GPIO enable line for the IMX335 camera via a GPIO hog
in order to ensure it is well enabled.

Use scmi_v3v3 for imx335 regulators.
The 3 imx335 supplies are generated within the MB1854 and all come
from the v3v3 coming from the board.  Ensure that this regulator is
enabled by using the scmi_v3v3 as supplier of the imx335.

Signed-off-by: Hugues Fruchet <hugues.fruchet@foss.st.com>
Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
---
 arch/arm64/boot/dts/st/stm32mp257f-ev1.dts | 40 ++++++++++--------------------
 1 file changed, 13 insertions(+), 27 deletions(-)

diff --git a/arch/arm64/boot/dts/st/stm32mp257f-ev1.dts b/arch/arm64/boot/dts/st/stm32mp257f-ev1.dts
index 12b4018edeb0..acc730146287 100644
--- a/arch/arm64/boot/dts/st/stm32mp257f-ev1.dts
+++ b/arch/arm64/boot/dts/st/stm32mp257f-ev1.dts
@@ -72,30 +72,6 @@ ddr_channel: sdram-channel-0 {
 		io-width = <32>;
 	};
 
-	imx335_2v9: regulator-2v9 {
-		compatible = "regulator-fixed";
-		regulator-name = "imx335-avdd";
-		regulator-min-microvolt = <2900000>;
-		regulator-max-microvolt = <2900000>;
-		regulator-always-on;
-	};
-
-	imx335_1v8: regulator-1v8 {
-		compatible = "regulator-fixed";
-		regulator-name = "imx335-ovdd";
-		regulator-min-microvolt = <1800000>;
-		regulator-max-microvolt = <1800000>;
-		regulator-always-on;
-	};
-
-	imx335_1v2: regulator-1v2 {
-		compatible = "regulator-fixed";
-		regulator-name = "imx335-dvdd";
-		regulator-min-microvolt = <1200000>;
-		regulator-max-microvolt = <1200000>;
-		regulator-always-on;
-	};
-
 	memory@80000000 {
 		device_type = "memory";
 		reg = <0x0 0x80000000 0x1 0x0>;
@@ -253,6 +229,16 @@ phy0_eth2: ethernet-phy@1 {
 	};
 };
 
+&gpioi {
+	/* Enable the IMX335 power line */
+	imx335-en-hog {
+		gpio-hog;
+		gpios = <0 GPIO_ACTIVE_HIGH>;
+		output-high;
+		line-name = "imx335_en";
+	};
+};
+
 &i2c2 {
 	pinctrl-names = "default", "sleep";
 	pinctrl-0 = <&i2c2_pins_a>;
@@ -269,9 +255,9 @@ imx335: camera@1a {
 		compatible = "sony,imx335";
 		reg = <0x1a>;
 		clocks = <&clk_ext_camera>;
-		avdd-supply = <&imx335_2v9>;
-		ovdd-supply = <&imx335_1v8>;
-		dvdd-supply = <&imx335_1v2>;
+		avdd-supply = <&scmi_v3v3>;
+		ovdd-supply = <&scmi_v3v3>;
+		dvdd-supply = <&scmi_v3v3>;
 		reset-gpios = <&gpioi 7 (GPIO_ACTIVE_LOW | GPIO_PUSH_PULL)>;
 
 		port {

-- 
2.34.1

[PATCH 3/4] arm64: dts: st: use video-interfaces media bus type in stm32mp257f-ev1

[Alain Volmat]

Use MEDIA_BUS_TYPE macro in stm32mp257f-ev1 for csi/dcmipp bus-type.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
---
 arch/arm64/boot/dts/st/stm32mp257f-ev1.dts | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/st/stm32mp257f-ev1.dts b/arch/arm64/boot/dts/st/stm32mp257f-ev1.dts
index acc730146287..782b4bb843ee 100644
--- a/arch/arm64/boot/dts/st/stm32mp257f-ev1.dts
+++ b/arch/arm64/boot/dts/st/stm32mp257f-ev1.dts
@@ -8,6 +8,7 @@
 
 #include <dt-bindings/gpio/gpio.h>
 #include <dt-bindings/leds/common.h>
+#include <dt-bindings/media/video-interfaces.h>
 #include <dt-bindings/regulator/st,stm32mp25-regulator.h>
 #include "stm32mp257.dtsi"
 #include "stm32mp25xf.dtsi"
@@ -161,7 +162,7 @@ port@0 {
 			csi_sink: endpoint {
 				remote-endpoint = <&imx335_ep>;
 				data-lanes = <1 2>;
-				bus-type = <4>;
+				bus-type = <MEDIA_BUS_TYPE_CSI2_DPHY>;
 			};
 		};
 		port@1 {
@@ -178,7 +179,7 @@ &dcmipp {
 	port {
 		dcmipp_0: endpoint {
 			remote-endpoint = <&csi_source>;
-			bus-type = <4>;
+			bus-type = <MEDIA_BUS_TYPE_CSI2_DPHY>;
 		};
 	};
 };

-- 
2.34.1

[PATCH 4/4] arm64: dts: st: add imx335/csi/dcmipp nodes on stm32mp235f-dk

[Alain Volmat]

Add all nodes necessary for the imx335 camera capture via csi / dcmipp
on stm32mp235f discovery board.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
---
 arch/arm64/boot/dts/st/stm32mp235f-dk.dts | 75 +++++++++++++++++++++++++++++++
 1 file changed, 75 insertions(+)

diff --git a/arch/arm64/boot/dts/st/stm32mp235f-dk.dts b/arch/arm64/boot/dts/st/stm32mp235f-dk.dts
index dd4efbe5a46e..f06b334dc9ce 100644
--- a/arch/arm64/boot/dts/st/stm32mp235f-dk.dts
+++ b/arch/arm64/boot/dts/st/stm32mp235f-dk.dts
@@ -9,6 +9,7 @@
 #include <dt-bindings/gpio/gpio.h>
 #include <dt-bindings/input/input.h>
 #include <dt-bindings/leds/common.h>
+#include <dt-bindings/media/video-interfaces.h>
 #include "stm32mp235.dtsi"
 #include "stm32mp23xf.dtsi"
 #include "stm32mp25-pinctrl.dtsi"
@@ -27,6 +28,14 @@ chosen {
 		stdout-path = "serial0:115200n8";
 	};
 
+	clocks {
+		clk_ext_camera: clk-ext-camera {
+			#clock-cells = <0>;
+			compatible = "fixed-clock";
+			clock-frequency = <24000000>;
+		};
+	};
+
 	gpio-keys {
 		compatible = "gpio-keys";
 
@@ -131,6 +140,42 @@ &arm_wdt {
 	status = "okay";
 };
 
+&csi {
+	vdd-supply =  <&scmi_vddcore>;
+	vdda18-supply = <&scmi_v1v8>;
+	status = "okay";
+
+	ports {
+		#address-cells = <1>;
+		#size-cells = <0>;
+		port@0 {
+			reg = <0>;
+			csi_sink: endpoint {
+				remote-endpoint = <&imx335_ep>;
+				data-lanes = <1 2>;
+				bus-type = <MEDIA_BUS_TYPE_CSI2_DPHY>;
+			};
+		};
+		port@1 {
+			reg = <1>;
+			csi_source: endpoint {
+				remote-endpoint = <&dcmipp_0>;
+			};
+		};
+	};
+};
+
+&dcmipp {
+	status = "okay";
+
+	port {
+		dcmipp_0: endpoint {
+			remote-endpoint = <&csi_source>;
+			bus-type = <MEDIA_BUS_TYPE_CSI2_DPHY>;
+		};
+	};
+};
+
 &ethernet1 {
 	pinctrl-0 = <&eth1_rgmii_pins_b>;
 	pinctrl-1 = <&eth1_rgmii_sleep_pins_b>;
@@ -153,6 +198,16 @@ phy1_eth1: ethernet-phy@1 {
 	};
 };
 
+&gpiob {
+	/* Enable the IMX335 power line */
+	imx335-en-hog {
+		gpio-hog;
+		gpios = <11 GPIO_ACTIVE_HIGH>;
+		output-high;
+		line-name = "imx335_en";
+	};
+};
+
 &i2c2 {
 	pinctrl-names = "default", "sleep";
 	pinctrl-0 = <&i2c2_pins_b>;
@@ -165,6 +220,26 @@ &i2c2 {
 	/delete-property/dmas;
 	/delete-property/dma-names;
 
+	imx335: camera@1a {
+		compatible = "sony,imx335";
+		reg = <0x1a>;
+		clocks = <&clk_ext_camera>;
+		avdd-supply = <&scmi_v3v3>;
+		ovdd-supply = <&scmi_v3v3>;
+		dvdd-supply = <&scmi_v3v3>;
+		reset-gpios = <&gpiob 1 (GPIO_ACTIVE_LOW | GPIO_PUSH_PULL)>;
+		status = "okay";
+
+		port {
+			imx335_ep: endpoint {
+				remote-endpoint = <&csi_sink>;
+				clock-lanes = <0>;
+				data-lanes = <1 2>;
+				link-frequencies = /bits/ 64 <594000000>;
+			};
+		};
+	};
+
 	ili2511: ili2511@41 {
 		compatible = "ilitek,ili251x";
 		reg = <0x41>;

-- 
2.34.1

Re: [PATCH 2/4] arm64: dts: st: ensure IMX335 is enabled on stm32mp257f-ev1

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Using a GPIO hog to enable the camera's local regulator bypasses the regulator framework, breaking runtime power management and risking power sequencing violations.
--

commit b096d3a18793729d58affdc2e7b576dc33241f8d
Author: Alain Volmat <alain.volmat@foss.st.com>

arm64: dts: st: ensure IMX335 is enabled on stm32mp257f-ev1

This commit removes the dedicated fixed regulators for the IMX335 camera
and instead routes its supplies directly to the system scmi_v3v3 supply.
It also adds a GPIO hog to unconditionally drive the camera's enable pin high.

> diff --git a/arch/arm64/boot/dts/st/stm32mp257f-ev1.dts b/arch/arm64/boot/dts/st/stm32mp257f-ev1.dts
> --- a/arch/arm64/boot/dts/st/stm32mp257f-ev1.dts
> +++ b/arch/arm64/boot/dts/st/stm32mp257f-ev1.dts
[ ... ]
> +&gpioi {
> +	/* Enable the IMX335 power line */
> +	imx335-en-hog {
> +		gpio-hog;
> +		gpios = <0 GPIO_ACTIVE_HIGH>;
> +		output-high;
> +		line-name = "imx335_en";
> +	};
> +};

[Severity: Medium]
Does using a GPIO hog here bypass the regulator framework and break runtime
power management? 

Since the hog forces the regulator's enable pin HIGH unconditionally as soon
as the GPIO controller probes, the camera module appears to be powered on at
all times. Does this defeat the IMX335 driver's runtime PM which attempts to
manage the power sequences to save power?

[ ... ]
>  imx335: camera@1a {
>  		compatible = "sony,imx335";
>  		reg = <0x1a>;
>  		clocks = <&clk_ext_camera>;
> -		avdd-supply = <&imx335_2v9>;
> -		ovdd-supply = <&imx335_1v8>;
> -		dvdd-supply = <&imx335_1v2>;
> +		avdd-supply = <&scmi_v3v3>;
> +		ovdd-supply = <&scmi_v3v3>;
> +		dvdd-supply = <&scmi_v3v3>;
>  		reset-gpios = <&gpioi 7 (GPIO_ACTIVE_LOW | GPIO_PUSH_PULL)>;

[Severity: Medium]
By pointing the camera's supplies directly to the system supply instead of a
fixed regulator that owns the enable GPIO, will the runtime PM toggle requests
from the IMX335 driver be ignored by the actual hardware?

If the main scmi_v3v3 supply is disabled during suspend while the GPIO block
remains active, the EN pin might be driven HIGH into an unpowered regulator.
Could this risk hardware back-powering via ESD diodes?

Should this enable GPIO be modeled as a fixed regulator instead of a hog to
maintain proper power sequencing?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260914-stm32mp2-dk-camera-v1-0-2f2bd719bb63@foss.st.com?part=2

Re: [PATCH 1/4] arm64: dts: st: add imx335/csi/dcmipp nodes on stm32mp257f-dk

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Using a `gpio-hog` to enable the IMX335 power line circumvents the camera driver's runtime power management.
--

commit 933d75b3c84530835787fe0315d18eced64336b3
Author: Alain Volmat <alain.volmat@foss.st.com>

arm64: dts: st: add imx335/csi/dcmipp nodes on stm32mp257f-dk

This commit adds all nodes necessary for the imx335 camera capture via CSI
and DCMIPP on the stm32mp257f discovery board.

> diff --git a/arch/arm64/boot/dts/st/stm32mp257f-dk.dts b/arch/arm64/boot/dts/st/stm32mp257f-dk.dts
> index 8daf3dfd51339..39ad23d95069c 100644
> --- a/arch/arm64/boot/dts/st/stm32mp257f-dk.dts
> +++ b/arch/arm64/boot/dts/st/stm32mp257f-dk.dts

[ ... ]

> @@ -160,6 +205,16 @@ phy1_eth1: ethernet-phy@1 {
>  	};
>  };
>  
> +&gpiob {
> +	/* Enable the IMX335 power line */
> +	imx335-en-hog {
> +		gpio-hog;

[Severity: Medium]
Does using a gpio-hog to enable the IMX335 power line circumvent the camera
driver's runtime power management?

By permanently asserting the power line upon boot, the IMX335 camera sensor
remains fully powered at all times, preventing the system from reducing power
draw when the camera is not active. This wastes energy and breaks the expected
runtime power management.

> +		gpios = <11 GPIO_ACTIVE_HIGH>;
> +		output-high;
> +		line-name = "imx335_en";
> +	};
> +};
>  
>  &i2c2 {

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260914-stm32mp2-dk-camera-v1-0-2f2bd719bb63@foss.st.com?part=1